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121.
Changes in healthcare today have called for leadership styles that place a heavy demand on organizations. Shifts in markets and reimbursement strategies call for new leaders with vision that can guide healthcare organizations to change. In a postmodern era, organizations see the transformational leader as a valuable asset in changing times. This article addresses the foundations of the transformational leader metanarrative and, through a postmodern discourse, deconstructs the concept. The article presents a review of postmodern thought in relation to the metanarrative of leadership and applications to nursing administration.  相似文献   
122.
123.
Hauff P  Reinhardt M  Briel A  Debus N  Schirner M 《Radiology》2004,231(3):667-673
PURPOSE: To evaluate the feasibility of using intravenously administered L-selectin ligand-specific polymer-stabilized air-filled microparticles (MPs) for active targeting of peripheral lymph nodes under normal conditions in animal models. MATERIALS AND METHODS: L-selectin ligand-specific MPs and two control substances (immunoglobulin M-isotype MPs and native MPs) were each administered in three conscious mice as a single intravenous bolus injection (1.4 x 10(7) MPs/kg). All mice were sacrificed 30 minutes after administration. Lymph nodes (cervical, inguinal, axillary, popliteal, mesenteric), spleen (positive control), and kidney (blood pool control) were removed and examined for MP-related stimulated acoustic emission (SAE) signals by using harmonic color Doppler ultrasonography (US) in a tank containing degassed water. A second experiment was performed in six anesthetized beagle dogs by using the same MP formulation. Each of the MP formulations was administered in two anesthetized dogs as a single intravenous bolus injection (1 x 10(7) MPs/kg). The popliteal lymph nodes, spleen (positive control), and kidney (blood pool control) were examined in vivo with US for MP-related SAE signals 30 minutes after administration. Fisher exact test for the one-side alternative was used for mouse data analysis. RESULTS: The lymph nodes of all mice (P =.05) and the popliteal lymph nodes of both dogs treated with L-selectin ligand-specific MPs showed clear MP-related SAE signals, whereas the lymph nodes of all mice and the popliteal lymph nodes of four dogs that received the control substances did not show any SAE signals. CONCLUSION: Use of an intravenously administered L-selectin ligand-specific US contrast agent is feasible for active lymph node targeting in mice and dogs.  相似文献   
124.
The primary contribution of Joseph Newhouse's paper is to make the point that it is impossible to devise a drug pricing policy that satisfies either the conditions for economic efficiency or prevailing standards of "fairness." Not specifically mentioned by Newhouse is a rule for the socially efficient outlays on selling and marketing by the pharmaceutical industry. In fact, it is not clear that the current allocation of the industry's revenue dollars to marketing and R&D is efficient from society's point of view. This paper explores this question and proposes an independent, publicly funded information infrastructure to study and disseminate results on pharmaceutical cost-effectiveness.  相似文献   
125.
BACKGROUND: Due to severe side effects in virtually all children treated with a standard dose of 45 mg/m(2)/day all-trans-retinoic acid (ATRA) for acute promyelocytic leukemia (APL) the AML-BFM study group reduced the dosage to 25 mg/m(2)/day. For the lack of data on the use of ATRA at this dosage in children with APL, the study group further decided to evaluate the pharmacokinetics and metabolism of ATRA in children. PROCEDURE: Twenty-three pharmacokinetic and metabolic profiles of ATRA were studied in 14 children (aged 0.9-18.4 years) with APL. Eleven plasma samples were collected over a period of 8 hr and analyzed for ATRA and its metabolites by high-performance liquid chromatography. RESULTS: Peak plasma concentrations of ATRA were characterized by wide interpatient variability (range: 28.6-513.0 nM). Compared to adults the same metabolic pathways were observed in children. Even though peak plasma concentrations were in the lower range of those considered effective in vitro, ATRA side effects, notably neurotoxicity, still required dose reduction, treatment break, or drug withdrawal in eight patients. In this small number of patients, neurotoxicity could not be related to age or any specific level of ATRA or metabolites in the plasma. Plasma concentrations of vitamin A, however, were significantly higher in those patients, who developed signs of neurotoxicity (P = 0.03, Mann-Whitney Rank Sum test). CONCLUSIONS: Considering the low plasma concentrations and the persistence of toxicity in spite of dose reduction intermittent dosing schedules might be considered as an alternative to further dose reduction of ATRA in the treatment of APL especially in children, who might be at risk of ATRA-induced neurotoxicity.  相似文献   
126.
Aims: To assess maternal compliance with nutritional recommendations in an allergy preventive programme, and identify factors influencing compliance behaviour. Methods: Randomised double-blind intervention study on the effect of infant formulas with reduced allergenicity in healthy, term newborns at risk of atopy. Maternal compliance with dietary recommendations concerning milk and solid food feeding was categorised. Results: A total of 2252 newborns were randomised to one of four study formulas. The drop out rate during the first year of life was 13.5% (n = 304). The rates of high, medium, and low compliance to milk feeding during weeks 1–16 were 83.4%, 4.0%, and 7.5%; the corresponding rates to solid food feeding during weeks 1–24 were 60.0%, 12.1%, and 22.9%. In 5.1% of subjects no nutritional information was available. Low compliance was more frequent among non-German parents, parents with a low level of education, young mothers, smoking mothers, and those who weaned their infant before the age of 2 months. Conclusions: Evaluation of allergy preventive programmes should take into account non-compliance for assessing the preventive effectiveness on study outcome.  相似文献   
127.
BACKGROUND: Minimal residual disease is a prognostic factor in AML. However, the impact on treatment stratification is not established. The AML-BFM 98 MRD study started in 1/2000 in order to evaluate, standardize and establish immunophenotyping in AML in children. METHODS: In a first phase the participating laboratories in Muenster, Goettingen, Vienna and Prague agreed on identical antibody-panels and standardized procedures of sample processing, analysis and data management. The consensus panel was evaluated and adapted to 3- and 4-color flowcytometry. The complete panel was applied to each follow-up sample in orderto minimize the risk offalse negative results due to the loss or shift of antigens during treatment, a known phenomenon in myeloid blasts. Between 1/2000 and 9/2001 165 of 198 protocol patients were analysed at diagnosis, in 149 children at least two follow-up samples were available. RESULTS: Three kinds of immunophenotypes could be defined. Asynchronous expression of stem cell and myeloid antigens i. e. CD34/CD117 combined with CD13/CD15 had a low specificity because precursors in regenerating or normal bone marrow expressed this pattern in 0.47 % (0.1 to 1.5 %). The aberrant co-expression of stem cell antigens and lymphatic antigens such as CD7 or CD2 showed a median level of specificity (0.07 % (0.04 to 0.19 %). Aberrant expression ofstem cell antigens combined with B-lymphatic (CD19, CD10) or NK-cell antigen (CD56) showed the best specificity. The maximal level in normal bone marrow was 0.05 %. Sensitivity of different immunophenotypes was evaluated by diluting known leukemic blasts in regenerating bone marrow. Minimal level of sensitivity was found to be at 10 (-3) to 5 x 10 (-4). According to these data highiy specific immunophenotypes could be detected in 33 %, median specificity was seen in 71 % and low specificity was seen in 88 % of the protocol patients. Two laboratories analyzed simultaneously 17 samples of children with AML from diagnosis and during therapy. A high correlation of blast quantification could be demonstrated (correlation r (2) = 0.98; blasts < 5 % r (2) = 0.91). In addition, two independent explorers quantified the raw data of 16 samples. All results correlated well (r (2) = 0.97; blasts < 5 % r (2) = 90.94). Conclusion: The prospective study phase, started 1/2002, aims to test the impact of MRD diagnostics as an independent prognostic factor in AML in children. This might facilitate future treatment stratification and consequently optimize outcome.  相似文献   
128.
BACKGROUND: First-line treatment in AML commonly included high cumulative doses of anthracyclines with an increasing risk of cardiotoxicity. Liposomal daunorubicin (L-DNR) is thought to be less cardiotoxic without impairment of efficacy. METHODS: The AML-BFM REZ 97 study included two reinduction blocks with L-DNR (2 x 60 mg/m (2) n = 38, since 2/1999 3 x 60 mg/m (2) n = 31) combined with cytarabine (500 mg/m (2) 4 d). Children who achieved a second blast clearance were allocated to allogeneic stem cell transplantation either from a matched related (MRD) or a matched unrelated donor (MUD). Lack of a donor justified haploidentical SCT in early relapse (1st remission < 1 year) and autologous SCT in late relapse. PATIENTS: Between 1/1997 and 9/2001, 69 children were enrolled in the AML-BFM 97 relapse study. The median duration of first remission was 0.9 years. Forty-one patients had a remission of less than one year, 28 of more than a year. RESULTS: 46 children (67 %) achieved a second remission, defined as clearance of blasts in bone marrow and at least a partial hematological reconstitution. Seventeen of these children are alive (12 of 25 children receiving allogeneic SCT (MFD/MUD); 1 of 8 children after haploidentical SCT; 1 of 4 patients after autologous SCT and 3 of 9 patients treated with chemotherapy only). Further three children without 2nd remission survived after MFD-SCT (n = 2) or chemotherapy (n = 1; follow-up 0.3 to 0.7 years). Duration of first remission remains a significant prognostic factor. The pharmacokinetic investigation showed a high overall AUC of 234.6 mg/l h at a dose of 60 mg/m (2), and a volume of distribution of 1.98 l/m (2), which is much lower in comparison to conventional Daunorubicin. Regarding toxicity, the combination of L-DNR and cytarabine followed by SCT was feasible in experienced centers, however, acute complications like infection or septicemia in aplasia, mucositis and GvHD were common. By contrast, no clinical relevant cardiotoxicity was seen so far, but definitive results in long-term cardiotoxicity await a longer follow-up. In conclusion, L-DNR/cytarabine treatment induced a 2nd remission in most of the children with relapsed or refractory AML. It has to be followed by allogeneic SCT which enables long-term survival.  相似文献   
129.
RATIONALE AND OBJECTIVES: Efforts to establish a quantitative approach to the computed tomography (CT)-based character ization of the lung parenchyma in interstitial lung disease (including emphysema) has been sought. The accuracy of these tools must be site independent. Multi-detector row CT has remained the gold standard for imaging the lung, and it provides the ability to image both lung structure as well as lung function. MATERIAL AND METHODS: Imaging is via multi-detector row CT and protocols include careful control of lung volume during scanning. Characterization includes not only anatomic-based measures but also functional measures including regional parameters derived from measures of pulmonary blood flow and ventilation. Image processing includes the automated detection of the lungs, lobes, and airways. The airways provide the road map to the lung parenchyma. Software automatically detects the airways, the airway centerlines, and the branch points, and then automatically labels the airway tree segments with a standardized set of labels, allowing for intersubject as well intrasubject comparisons across time. By warping all lungs to a common atlas, the atlas provides the range of normality for the various parameters provided by CT imaging. RESULTS: Imaged density and textural changes mark underlying structural changes at the most peripheral regions of the lung. Additionally, texture-based alterations in the parameters of blood flow may provide early evidence of pathologic processes. Imaging of stable xenon gas provides a regional measure of ventilation which, when coupled with measures of flow, provide for a textural analysis regional of ventilation-perfusion matching. CONCLUSION: With the improved resolution and speed of CT imaging, the patchy nature of regional parenchymal pathology can be imaged as texture of structure and function. With careful control of imaging protocols and the use of objective image analysis methods it is possible to provide site-independent tools for the assessment of interstitial lung disease. There remains a need to validate these methods, which requires interdisciplinary and cross-institutional efforts to gather appropriate data bases of images along with a consensus on appropriate ground truths associated with the images. Furthermore, there is the growing need for scanner manufacturers to focus on not just visually pleasing images, but on quantitatifiably accurate images.  相似文献   
130.
OBJECTIVE: Compare the efficacy, safety, and patient satisfaction of continuous subcutaneous insulin infusion (CSII) therapy with multiple daily injection (MDI) therapy for patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: A total of 132 CSII-naive type 2 diabetic patients were randomly assigned (1:1) to CSII (using insulin aspart) or MDI therapy (bolus insulin aspart and basal NPH insulin) in a multicenter, open-label, randomized, parallel-group, 24-week study. Efficacy was assessed with HbA(1c) and eight-point blood glucose (BG) profiles. Treatment satisfaction was determined with a self-administered questionnaire. Safety assessments included adverse events, hypoglycemic episodes, laboratory values, and physical examination findings. RESULTS: HbA(1c) values decreased similarly for both groups from baseline (8.2 +/- 1.37% for CSII, 8.0 +/- 1.08% for MDI) to end of study (7.6 +/- 1.22% for CSII, 7.5 +/- 1.22% for MDI). The CSII group showed a trend toward lower eight-point BG values at most time points (only significant 90 min after breakfast; 167 +/- 48 vs. 192 +/- 65 mg/dl for CSII and MDI, respectively; P = 0.019). A total of 93% of CSII-treated subjects preferred the pump to their previous injectable insulin regimen for reasons of convenience, flexibility, ease of use, and overall preference. Safety assessments were comparable for both treatment groups. CONCLUSIONS: Insulin aspart in CSII therapy provided efficacy and safety comparable to MDI therapy for type 2 diabetes. Patients with type 2 diabetes can be trained as outpatients to use CSII and prefer CSII to injections, indicating that pump therapy should be considered when initiating intensive insulin therapy for type 2 diabetes.  相似文献   
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